Cigarettes and their construction

ABSTRACT

A cigarette is provided with the tobacco column portion adjacent the filter assembly encased by a heat shrink material whereby as the burn approaches the butt the heat shrink material begins to contract radially and compress the encased tobacco column restricting the air flow therethrough. This reduces the diameter of burning column adjacent the filter assembly and thus extinguishes or at least confines the remaining tobacco in the cigarette.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of U.S. application Ser. No. 14/780,371filed Sep. 25, 2015, issued as U.S. Pat. No. 10,729,170 on Aug. 4, 2020,which is the U.S. national phase of PCT Application No.PCT/AU2014/000358 filed on Mar. 26, 2014, which claims priority to AUPatent Application No. 2013901067 filed on Mar. 27, 2013 and AU PatentApplication No. 2013204693 filed Apr. 12, 2013, the disclosures of whichare incorporated in their entirety by reference herein.

TECHNICAL FIELD

This invention relates to cigarettes, their construction and componentstherefore.

BACKGROUND

The disposal of cigarettes by casting away burning cigarettes withoutthought of the consequences can and often does cause damage. This mayrange from a burn mark in a floor or its covering, a house fire or inthe worst case a bush fire with sometimes dire consequences.

Cigarettes are most often smoked down to a short length whereupon theyare discarded with the remnants of the tobacco column alight. As such,the discarded butt constitutes a fire hazard. Many conscientious smokersstamp on the burning butt to extinguish it, while others may simplythrow the burning butt aside without thought of the possibleconsequences. As a result, the haphazard disposal of cigarettesconstitutes a significant damage threat to property and people.

Another frequent occurrence is damage to furniture by placing a burningbutt onto the surface of a piece of furniture. While such damage mayoften be only superficial it may significantly degrade the value of theburnt article which may, as a result of the burn, require costlyrepairs.

This invention aims to reduce the potential for damage being caused toproperty and people by improperly discarded cigarettes. This inventionfurther aims to provide cigarettes which, even when disposed ofhaphazardly as a burning butt, will self-extinguish so as to minimizethe risk of setting alight a flammable medium into or onto which theburning butt is discarded.

Many smokers only rarely discard cigarettes when the tobacco column iscompletely burnt away, leaving only the filter. While the reason forthis is not known by the applicant it is possible that the unburnttobacco column remaining behind the burning end acts as a preliminaryfilter of the nicotine laden smoke with the result that the nicotinecontent of the smoke gradually increases during smoking. As a result thetaste of the smoke becomes sufficiently unpleasant and, probablysubconsciously at that stage, the cigarette is discarded as a burningbutt. This results in the disposal of cigarettes which remain alight andthus have the potential to cause significant damage.

There have been studies conducted which suggest that much of theundesirable smoke pollutants which are puffed from a cigarette areinhaled during puffing the near end of the tobacco column. Thus anymeans which limits the smoke inhalation during the burn of the tobaccocolumn at the filter end has the potential to reduce inhalation of somepollutants from a cigarette.

A typical packet cigarette is made from a column of tobacco wrapped incigarette paper and joined to a filter plug by the wrap of tipping paperwhich overlaps a portion of the butt of the tobacco column, the filterplug medium itself being wrapped in a plug wrap. All of these componentsare assembled to form the particular property of a cigarette which isenjoyed by a smoker and a vast amount of money is spent promotingrespective brands and types each having a particular characteristicdetermined by the mix of factors of each element utilized in theconstruction of cigarettes.

This invention aims to provide improvements to cigarettes, componentstherefore and methods of manufacture which will alleviate at least oneof the abovementioned disadvantages.

SUMMARY

With the foregoing in view, this invention in one aspect resides in acigarette having its tobacco column butt portion encased by a shrinkablematerial which shrinks upon the application of heat thereto whereby asthe burning end of the cigarette approaches the butt the shrinkablematerial begins to contract and compress the encased tobacco columnrestricting the air flow therethrough.

Typically if a tobacco column in a cigarette rod has a length of about50 mm, the heat shrinkable material would extend along the butt portionthereof adjacent the filter for about 6 mm to 10 mm although this may bevaried as desired. The tobacco column may be configured so that in use,shrinking of the encasing material will provide a relatively suddenchange in the smoking characteristic of the cigarette when the burnreaches the heat shrinkable material. This may cause the smoker todiscard the cigarette at that stage of the burn at which substantiallyall the remaining unburnt tobacco will be confined within the encasingshrinkable material whereby it is made safer than a conventionalcigarette for careless discarding. This cause for disposal of thecigarette may result from the cigarette becoming unpleasant to smoke orfrom a noticeable change in a smoking characteristic of the cigaretteindicating to the smoker that concentrations of smoke pollutants areincreasing.

The heat shrinkable material when heated by the adjacent burning tobaccomay sufficiently compress the remaining tobacco column so as to confineit or deprive it of an air flow therethrough whereby it rapidlyextinguishes.

The heat shrinkable encasing material may extend further along thecolumn of tobacco and be arranged, such as by varying the thickness ofthe shrinkable material or its shrink properties, to shrinkprogressively or stepwise to reduce the air flow capacity through thecigarette as it is smoked and as a consequence provide a condition whichmay reduce the rate of smoke and nicotine intake when puffing on thereduced airflow portion of the cigarette or cause the smoker to discardthe cigarette before the burn reaches the butt of the tobacco column.Such an arrangement has the potential to reduce nicotine or otherpollutants derived from smoking a cigarette.

The encasing shrinkable material may be provided for the purpose ofreducing the column diameter of the cigarette rod adjacent the burn tosuch extent that damage caused by placing a burning cigarette butt ontoa flat surface will be prevented or reduced, as the heat shrinkablematerial will cause the burning portion of the rod to shrink away fromthe supporting surface whilst being supported by the filter assemblyresting on the surface.

If desired, along with the selection of characteristics of the heatshrinkable material, the density or configuration of the tobacco columnmay be varied, such as by its density being reduced or increased in thearea encased by the shrinkable material to achieve a desired result.Thus for example, the density may be reduced to achieve the desireddegree of necking of the still burning portion of the tobacco column orthe density may be increased to assist the necking result caused byshrinking of the encasing material to compressing the tobacco columnsufficiently to extinguish the encased tobacco or to achieve a desiredpre-filtering effect.

Many heat shrinkable materials are available both in tube form and insheet or tape form and many are used in confined areas such thatshrinkable material has been developed to make the fumes resultant fromthe heat shrink process non-toxic or at least sufficiently safe forhuman consumption and only such materials which are safe for use in thisapplication would be selected for use in the present invention. Howeverthe use of a shrinkable material with a specific taste may provide afurther signal to a smoker that for least harm to the smoker, thecigarette should be discarded at the point where the encasing materialcommences to react to the heat of the burning tobacco column.

The encasing shrinkable material may be applied to the cigarette in theform of a tube or it may be applied in the form of a wrap. Alternativelythe shrinkable material may be applied as a spray-on layer or as aliquid which dries to form the encasing layer.

In a preferred form the shrinkable material is applied as a tape duringthe cigarette forming process and it may be utilized to secure thetobacco column to the filter assembly. In one form the shrinkablematerial is formed as a tape combined with the tipping paper whereby itmay be supplied to the cigarette manufacture as a substitute tippingpaper so as to minimize manufacturing process changes in the manufactureof cigarettes.

Accordingly, in another aspect this invention resides in a tipping wrapincluding a layer or band of shrinkable material protruding from an edgeof a band of tipping paper. This forms a composite band of the heatshrinkable material and tipping paper which may be wrapped around thefilter and the tobacco column to connect them together and/or to form atube of heat shrinkable material extending along the butt of the tobaccocolumn.

For this purpose the tipping paper may be of conventional size and theshrinkable material may be laminated to the portion of the tipping paperwhich normally overlaps the tobacco column. Alternatively the width ofthe tipping paper may be reduced and the shrinkable material may overlapall or a significant portion of the tipping paper and be apertured alongthe overlapping area to enable the tipping paper to pass air, smoke orgases therethrough.

The shrinkable material may be formed to extend only along one side ofthe tipping paper and be utilized to be wound onto a single tobaccocolumn and filter assembly. Alternatively, the tipping paper of thisinvention may also be formed with shrinkable material extending alongboth sides of the tipping paper so as to permit the tipping paper to bewound onto opposed co-axial filter and tobacco columns in a processwhere the filters and tobacco columns are formed in joined co-axialpairs of cigarettes prior to separation between the adjacent filters.

This invention also resides in the methods of forming cigarettes asvariously described above.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that this invention may be more readily understood and put intopractical effect, reference will now be made to the accompanyingdrawings which illustrate typical embodiments of cigarettes made by themethods and or utilizing the components broadly described above, andwherein:

FIG. 1 is a perspective view of a cigarette formed according to oneaspect of this invention;

FIG. 2 illustrates a tipping paper made in accordance with one aspect ofthis invention;

FIG. 3 illustrates the configuration of a discarded butt of a cigarettemade in accordance with the embodiment of FIG. 1;

FIG. 4 is a perspective view of a cigarette formed according to anotheraspect of this invention, and

FIG. 5 illustrates an alternate form of tipping paper and method of itsinstallation onto opposed tobacco columns and filters.

DETAILED DESCRIPTION

Referring to FIG. 1 it will be seen that a cigarette 10 includes awrapped tobacco column 11 secured to a filter assembly 12 by tippingpaper 14 which is wrapped around the assembled filter assembly 12 andtobacco column 11 during a typical manufacturing process to join themtogether and to provide the filter wrap or tipping paper a smoker's lipscontact.

According to this invention, in this embodiment the tipping wrap 18, asillustrated in FIG. 2, includes a conventional tipping paper portion 15and an adjoining wrapping portion 16 formed from heat shrinkablematerial which when wrapped upon itself about the tobacco column 11forms an encasing tube which shrinks upon the application of heatthereto to a smaller diameter tube 19, as illustrated in FIG. 3,surrounding the unburnt tobacco and/or the ash from the burnt tobacco.For this purpose the heat shrinkable material is applied to the tippingpaper with its major shrinking axis extending parallel to its junctionwith the tipping paper 15.

The width of the tipping paper portion 15 is suitably about the same asthe length of the filter assembly 12 while the shrinkable wrappingportion 16 is sufficiently wide so as to extend along the butt portion17 of a tobacco column which is normally discarded with the filterassembly 12. For a cigarette having a tobacco column diameter in theorder of 7 mm to 9 mm the shrinkable wrapping portion 16 suitably has alength of between 6 mm to 12 mm. Suitably the shrinkable wrappingportion 16 is transparent but it may be of any desired color and it maybe printed with information desired to be displayed by the cigarettemanufacturer.

As illustrated in FIG. 2, the tipping wrap 18 is supplied as acontinuous roll 18 which may be wrapped around a former if desired orotherwise stored to enable it to be used as a substitute for theexisting tipping paper so as to minimize disruption to the manufacturingprocess in order to incorporate aspects of this invention into themanufacture of cigarettes.

When a cigarette 10 according to this embodiment is smoked down to itsbutt 17, the core heat generated by the burning tobacco will cause theencasing heat shrinkable wrap of the wrapping portion 16 to shrink as acontracting tube 19, reducing the area of the open end 20 thereof, asillustrated in FIG. 3, through which air and pollutants may be drawnthrough the filter assembly 12 by the smoker.

Depending on the selection of the properties of the heat shrinkablematerial utilized in the wrapping portion 16, the reacting heatshrinkable material will either render the cigarette unpleasant forfurther smoking such that much of the pollutants contained in a tobaccocolumn will not be inhaled, or the remaining tobacco burning with adiminished supply of oxygen or extinguished as a result of sufficientcompaction of the tobacco within the shrunk tube 19 will be containedwithin the wrap 16 and rendered relatively harmless. Thus if discardedcarelessly whilst alight into combustible material such as grass thebutt should not cause a fire as many combustible materials have to beheated to an elevated temperature before combustion occurs. Thisrequires the butt to remain alight for a relatively long period whichshould not occur in a cigarette according to this invention.

Further as illustrated in FIG. 3, a still burning butt in this form whenrested on its side upon a flat surface such as a table will be disposedwith its burning end 22 elevated above the table so that it will notheat the surface sufficiently to burn it.

In the cigarette 24 illustrated in FIG. 4, the heat shrinkableencasement 25 of the tobacco column 26 extends further along the columnthan in the cigarette illustrated in FIG. 1. Furthermore, this encasingtube 25 is graduated so that an outer portion, such as the end portion27, will not shrink as much as the adjacent portion 28 whereby duringsmoking, the encasing tube 25 will progressively reduce in diameter toconstrict and contain the burnt and burning tobacco column and ifdesired eventually extinguish the butt portion by sufficient compressionof the tobacco column to effectively prevent the through flow of airnecessary to maintain burning.

The encasing tube 25 could extend along a major or minor portion of thetobacco column depending on the effect to be achieved and thespecification of the heat shrinkable material used and of course theencasement could be applied as a formed tube to a manufactured cigaretteor it could be in the form of a band which could be positioned duringmanufacture or by a smoker at a selected position along the length ofthe column to extinguish the tobacco at that position.

In the FIG. 5 embodiment illustrated, a tipping wrap 30 has a centralband of tipping paper 31 and opposed side bands 32, 33 of shrinkablewrapping material each arranged with their respective major shrinkdirection extending longitudinally along the tipping wrap 30. Thecentral band of tipping paper is between 30 mm and 50 mm wide so that itmay span a pair of filter assemblies 34 arranged in end to end abuttingrelationship.

The bands of shrinkable wrapping material 32, 33 are each approximately10 mm wide and overlap the adjacent edges of the band of tipping paper31 by about 2 mm and are glued thereto along the overlap zone 37 by awarm set gum. Thus in a manufactured cigarette the formed shrinkabletubes 36 extend about 8 mm along the butt 38 of the tobacco column 39.

According to this method of the invention, opposed pairs of formedtobacco columns 39 and filter assemblies 34 are arranged co-axially inabutting relationship, as illustrated, and the tipping wrap 30 is woundonto the assembled tobacco columns 39 and filter assemblies 34. Afterwrapping, the formed cigarettes are separated by slitting the wrap 30between the opposed filter assemblies 34. If desired the tipping wrapcould be formed as a broad composite sheet formed of multiple bands oftipping wraps as illustrated in FIG. 5 arranged in side by siderelationship across the sheet or otherwise as required to suit themanufacturing process.

It will of course be understood that the above has been given by way ofillustrative example only and that all such modifications and variationsthereto as would be apparent to persons skilled in the art are deemed tofall within the broad scope and ambit of this invention as is defined inthe appended claims.

What is claimed is:
 1. A tipping paper wrap which may be fed from a rolland wound onto a column assembly including a tobacco column and aco-axially juxtaposed filter, the tobacco column having a butt portionextending axially from the filter, the wrap comprising: a band oftipping paper formed to wrap about the filter, and a band of heat shrinkmaterial protruding from one edge of the tipping paper and which onapplication to said respective column assembly extends beyond thejunction between the filter and the juxtaposed tobacco column to form anencasing heat shrink layer about the butt portion of the tobacco column.2. The tipping paper wrap as claimed in claim 1, wherein the band ofheat shrink material is formed to extend along a minor portion of thelength of the tobacco column.
 3. The tipping paper wrap as claimed inclaim 2, wherein the band of heat shrink material overlaps the adjacentedge portion of the filter paper and extends therefrom for a distance ofbetween 5 mm and 10 mm.
 4. The tipping paper wrap for simultaneousapplication to a pair of oppositely arranged respective columnassemblies each including a tobacco column and a filter arranged withtheir respective filters in substantially co-axial abuttingrelationship, said wrap having one side portion forming a tipping paperwrap as claimed in claim 1 for application to one said column assemblyand an opposite side portion forming a tipping paper wrap forapplication to the other said column assembly.
 5. A method of joining atobacco column to a co-axially juxtaposed filter including providing atipping paper wrap as claimed in claim 1 and winding the tipping paperwrap onto the juxtaposed tobacco column and filter to form an encasinglayer of heat shrink material which spans the joint between the tobaccocolumn and the filter to join them together.
 6. The method as claimed inclaim 5, wherein the coaxially juxtaposed tobacco column and filter arerotated about their common longitudinal axes to wind the tipping paperwrap thereabout.
 7. The method as claimed in claim 5, wherein thetipping paper wrap is simultaneously wound onto a pair of tobaccocolumns and their respective filers arranged in a coaxial array withtheir filters adjoining one another.
 8. The method of joining a tobaccocolumn to a co-axially juxtaposed filter comprising providing a tippingpaper wrap as claimed in claim 1 and winding the tipping paper wrap ontothe juxtaposed tobacco column and filter to join them together and toform an encasing layer of heat shrink material about the butt of thetobacco column.
 9. A cigarette made in accordance with the method ofclaim
 5. 10. A tipping wrap for use in the manufacture of cigarettes,comprising: central band of tipping paper having a width which can spana pair of abutting coaxially aligned filter assemblies; and a pair ofopposed side bands of heat shrinkable wrapping material affixed toopposite sides of the central band of tipping paper; wherein onapplication to the coaxially aligned filter assemblies the side bands ofheat shrinkable wrapping material extend beyond the junction between thefilter and a juxtaposed tobacco column to form an encasing heat shrinklayer about the butt portion of the tobacco column.
 11. The tipping wrapof claim 10, wherein pair of opposed side bands overlap and are glued tothe central band of tipping paper.
 12. The tipping wrap of claim 11,wherein pair of opposed side bands extends a distance of between 5 mmand 10 mm beyond the sides of the central band of tipping paper.